Delayed post rendering in feeds

In the video, the plain text version of a post is rendered alongside the FeedItem component. The FeedItem rendering is delayed for some reason (starting from the 3rd visit), which makes the feed navigation feel a bit slow:

delayed-post-rendering

      <FeedItem::Index
        @feedItem={{status}}
        @hideUnseen={{true}}
        @posinset={{add index 1}}
        @setsize={{this.model.feed.content.length}}
      />
      <div style="padding: 10px; border: 1px solid #555; margin: 2px;">
        <h4 style="font-size: 12px; color: #222;">
          {{status.id}}
        </h4>
        <p>
          {{status.content}}
        </p>
      </div>